Generation of egg white/carrageenan microparticles by droplet-based microfluidics

Abstract

Microparticles capable to transport and release bioactive compounds are being increasingly used in the food industry, as they provide functionalities for a variety of applications. At the same time, droplet-based microfluidics is becoming a powerful technology for producing engineered microparticles. This work reports on the development and use of microfluidic devices for the efficient generation of hybrid protein/polysaccharide microparticles. Microfluidic chips were designed and fabricated in our laboratory by laser micromachining on crystalline poly-methyl methacrylate. The chips were used for the generation of egg white/carrageenan droplets in oil phase, which were loaded with a model active component to analyze the transport and release capacities. The protein/polysaccharide droplets were cured by using either chemical (glutaraldehyde-induced crosslinking)or physical (microwave radiation-induced crosslinking)procedures. The generated microparticles had diameters in the range of 200?220 μm and were stable for several months, retaining the encapsulated hydrophilic active in oil medium. No surfactant was necessary neither for the droplet-based generation nor the storing. Different release profiles were attained after each curing process, which provides a great potential for the production of engineered microparticles for specific applications.